Red Flags: AFC West

The biggest remaining issue for the Broncos, Chiefs, Raiders and Chargers

Jim Rogash/Getty ImagesJoe Mays struggled at middle linebacker last season for the Denver Broncos. Will he start this season?

Welcome to the 2013 version of Insider's offseason staple series: Red Flags. This is the fourth of an eight-part examination in which Football Outsiders identifies the biggest remaining issue for every NFL team, division by division, after the NFL draft.

In 2012, Football Outsiders ranked Denver's rush defense among the league's best. They were fourth overall in run defense by Football Outsiders' DVOA (defense-adjusted value over average) metric, as well as third in second-level yards and first in open-field yards. The last two metrics show how productive Denver's linebackers and the secondary are at stopping the run once it breaks into the second level. To add further evidence, Denver's defensive adjusted line yards (ALY) for runs directed between the guards ranked sixth in the league.

To read the rest of Football Outsiders' analysis of the biggest remaining issue for AFC West teams, you must be an ESPN Insider.